White House on Climate, Heat Deaths–21jh.,b28
In a recent “fact sheet” on the threat climate change poses to human health, the White House cherry-picked data on the estimated number of premature deaths due to future extreme temperatures:
- The White House cited a nationwide model that predicts roughly 11,000 deaths in 2030 and more than 27,000 deaths in 2100 from extreme heat exposure compared with a 1990 baseline. But it ignores another model from the same study that predicts significantly fewer premature deaths – 6,950 in 2030 and 19,509 in 2100.
- The White House also ignored that the study predicts a decrease in the number of premature deaths from extreme cold temperatures. The net number of additional deaths from extreme temperatures in the model cited by the White House are 4,665 in 2030 and 9,632 in 2100.
- The White House makes no mention of the role that future adaptation could play in reducing deaths from extreme heat, such as greater accessibility to air conditioning and increased vegetation in cities.
The April 4 fact sheet announced the Obama Administration’s release of a new report from the U.S. Global Change Research Program called “The Impacts of Climate Change on Human Health in the United States.” Established in 1989 and mandated by Congress in 1990, the USGCRP is a “confederation” of research teams from 13 federal departments and agencies, including NASA and the Environmental Protection Agency.
We’ll first address the observed trends in premature deaths due to temperature extremes. We’ll then explain what the two models cited by the USGCRP report predict for the 21st century and what scientists know about how future adaptation could reduce the number deaths due to extreme heat.
As the USGCRP’s report explains, the “U.S. average temperatures have increased by 1.3°F to 1.9°F” since 1895 due to elevated greenhouse gas emissions. Accordingly, “heat waves have become more frequent and intense, and cold waves have become less frequent across the nation.” With a 3°F to 10°F increase by 2100, scientists predict these. For example, death records from 2006 to 2010 show roughly 1,300 deaths per year from extreme cold and 670 deaths per year from extreme heat in the U.S., according to the report (pages 47, 49). However, statistical approaches have estimated more than 1,300 deaths per year in the U.S. due to extreme heat from 1975 to 2004.
Studies have also shown that Americans have been adapting to temperature extremes over time. One paper, published online in the journal Natural Hazards on June 27, 2010, looked at U.S. Census and temperature data from 1975 to 2004 and found that extreme heat-related death rates have declined since 1996.
Thus, in its fact sheet, the White House correctly states: “Extreme heat can be expected to cause an increase in the number of premature deaths, from thousands to tens of thousands, each summer, which will outpace projected decreases in deaths from extreme cold.”
But the White House then goes on to cherry-pick data from one model discussed in the report: “One model projected an increase, from a 1990 baseline for more than 200 American cities, of more than an additional 11,000 deaths during the summer in 2030 and more than an additional 27,000 deaths during the summer in 2100.”
The USGCRP report cites two models from a study published online in Environmental Health on Nov. 4, 2015. Compared to a 1990 baseline, one model predicts an increase of 11,646 premature deaths from extreme heat and a reduction of 6,981 deaths from extreme cold in 2030, bringing the net number of deaths due to extreme temperature to 4,664. For 2100, this model predicts an increase of 27,312 deaths from extreme heat and a reduction of 17,680 deaths from extreme cold, with the net number of deaths at 9,632.
The second model predicts an increase of 6,950 premature deaths from extreme heat and a decrease of 5,207 deaths from extreme cold for 2030. This brings the net number of deaths from extreme temperatures to 1,743 compared with a 1990 baseline. For 2100, the second model projects an increase of 19,509 deaths from extreme heat and a decrease of 16,468 from extreme cold, with the net number of deaths at 3,042.
It is worth noting that the USGCRP report states scientists have “high confidence” that heat deaths will increase in the future, based on agreement among “a large number of studies as well as consistency across scenarios and regions.” Since fewer studies have looked at winter mortality and some research suggests “winter mortality is not strongly linked to temperatures,” scientists have “medium confidence” that cold-related deaths will decrease in the future.
“Will reduce the projected increase in deaths from heat.” Yet the White House makes no mention of this finding in its fact sheet.
One study, published online in Climatic Change on March 23, 2012, found that adaptation may reduce heat-related mortality by 37 percent to 56 percent in nine regions across California in the 2090s. The study, conducted by Laurence S. Kalkstein, a public health expert at the University of Miami, and others, cites both physiological and behavioral adaptations, including the body’s ability to adjust to gradual increases in temperature over time and increased access to air conditioning, respectively.
To sum up, the White House cherry-picked data on premature deaths from extreme temperatures in the future. Not only did its “fact sheet” on the subject solely cite results from the more extreme model, but it also failed to note future decreases in premature deaths due to milder winters and adaption.
source-sci check, staatton foundation, brian stone jr, plos one, fact check.org., vanessa schipani, natural hazards